Typewriting machine



Feb. 5, 1929.

H. A. AVERY ET AL TYPEWRITING MACHINE Filed Nov. 15,- 1926 4Sheets-Sheet Feb. 5, 1929.

H. A. AVERY El' AL TYPEWRITING MACHINE Filed Nov. 13, 1926 4Sheets-Sheet 2 ATTORNEYS l.. 7.. ILSE.

Feb. 5, 1929.

-.H. A. AVERY ET AL TYPEWRITING' MACHINE Filed Nov. 13, 1926 4Sheets-Sheet ATTORN EYS Feb. 5, 1929. 1,700,628

H. A. AVERY ET AL TYPEWRITING MACHINE Filed Nov. 13, 1926 4 Sheets-Sheet4.

Illu )III IIHIIII INVENTORS EA.AVe1:y; Jetamam 525.@ 011 A BY n IATTORNEYSh Patented Feb. 5, 192.9.

UNITED sTATEs PATE, OFFic HENRY ALLEN AVERY, OTTO rETERMANN, AND EDWINL. TIAEMON,y OE GEOTON,

NEW YOEK, AssreNoRs, EY MEsNE ASSIGNMENTS, To E c sMiTH a OOEONA TYPE-wEITEEs INC., OE sYEAcUsENEw YORK, A OOEPOEATION OE NEW YOEK.

TYPEWEITING MACHINE.

.Application iled November 13, 1926. Serial lNo. 148,257.

This invention relates to improvements in typewriting machines, and moreparticularly to platen carriage feed mechanism for such machines.

The'invention has for its principal'objects to provide an `improvedescapement mechanism; to provide an efcient rotary escape-` mentmechanism of simple and inexpensive construction; to provide meansconsisting 'of a minimum number of parts,l and of light and inexpensiveconstruction; whereby the carriage may be fed step-by-step to therightand to the left and may be given a continuous or running movement totheright and to vthe left; to Vprovide a' combined releasing andcontrolling means for the dog rocker of an escapement; to provideef'icient means for controlling the vthrow of the dog rocker; to providesimple and light dog-rocker-tripping 'means for releasing a carriage theletter-feed movement of which is controlled by a rotary escapement; toprovide an escap'ementl operable independently from a type-bar actuateduniversal bar and a space bar; to providea rotary escapement which may-Ybe readily yassembledand disassembled; and to provide carriageyfeeding and releasing means especially adapted for use in a low andcompact portable typewriting machine having a shifting platen carriage.

To the above and other ends, which will hereinafter appear,` theinvention consists in the features of construction, arrangements ofparts, and combinations of elements particularly pointed out in theclaims, and more fully hereinafter described.

In the'drawings, wherein the preferred embodiment of the invention isillustrated.

Fig. 1 is a vertical longitudinal sectional view of a portablethree-quarter strike typewriter in which'the improvements are embodied,the parts being innormal position;

Fig. v2 a detail viewshowing parts ofthe case shift means inperspective;

' 3 a detail sectional view of partfof the case shiftmeans; l. i

Figli va rear view ofthe machine on a Iieduced lscale/with certain partsbroken away. kand as `seen at an angle perpendicular to theinclined'partition wall of the main frame; Fig.l 5 a fragmentaryperspective view of the machine withV thel partsY in normal Vvposirige;l

Fig. 6 a-fragmentary plan vview of the ma'- chine with the platencarriage removed;

lFig. 7 a vertical sectional lview with Vthe parts positionedgas at ytheVend of af printing stroke of a type-bar;

Fig. 8 a Vvertical sectionalview,

'showingM the e-scapement released; l

Fig. 9 a bottom plan view of the escapement device with the parts innormal position;

Fig. 10a

Fig. 11 a bottom plan view of the-escape@ ment device with the partspositioned as in Fig. 7;

l1; l .Y V

Fig. 13 a bottom -plan view showing the. action of the escapement wheeland loose .dog during a continuous return movement of the carriage, or aback-spacing movement of the carriage bythe back-space key mechanism; lFig.' 14a section on vthe line 14e-14' of Fig.'13; "y

Fig. 15 a view ofthe escapement devic'eas seen-from the rear at an angleperpendicularA tofthe' pla-ne of case-shift movementof the shift frame;Y

" Fig. 16 a detail perspective viewshowing theindependent operatingconnections yof thev space bar and kuniversal bar with the dog rocker;and

Fig; 17 a detail view showing partsof the escapement mechanism intached. Y `The improvements have beenillustrated in connection with aportable threequarter strike typewriting machine having amain frame, atype-bar actioma shift`frame, and

perspective and desection'on the line U10-10 of i VF'g."12 a section onthe line 10Q-#12 of Fig.k

a platen carriage mounted on the shift frame, all constructed andarranged'as -in the well known Corona Four'typewriting machine, andasdisclosed in the ap lication lof 4131.13. Ely andE. L. Harmon,` filedOctober 31,1925. l

' Theman frame comprises a front'wallglO, aback wall 11, side walls 12,and a transverse partition wall 13. Wall 13 lies in an upemi No. 66,000,Y

l wardly and rearwardly inclined plane inthe rearportion of the 'mainframe with the lower 1 edge of the wallvabove thel level of the lower'edges' of the remaining frame walls. A type l bar rsegment 111 lies ina plane parallel with wall 13 and is'held to the front-face of said wallby .fastening screws with the usual curved pivot wire 16 for the typebars lying in a plane parallel with the plane of said wall.

to the rear face of wall 13 by fastening screws.`

The key levers 19 extend down behind wall 13 from wire 20, and thenforward under said wall to the front part of theframe, and are guided ina comb 22 held to the fframe. The connection between each type bar andits associated key lever comprises aV bell-crank lever 23, fulcrumed ina sub-lever segment 24 held tothe main frame, and links 25 and 26connecting said bell-crank at its opposite` ends with the type-bar heeland key lever, re-y spectively. Y l

' The shift frame comprises a vrearwardly y and downwardly inclinedcarriage bed 28 having a pair of downwardly and forwardly inclinedrguiding members 29 depending therefrom adjacent opposite sides of thema.- chine and located betweena pair ofsimilarly inclined guide members31 held to the main frame side walls 12.. Members 29 are connectedadjacent their lower ends by a transverse brace rod 30'. l

vThe platen oarriage27 ismounted onbed 28 in aI rearwardly tiltedposition to travel transversely of the'machine on forward ball bearings1 and a rear roller bearing 4. Bearings 1` are confined between racewaymembers 2 and 3'held to the carriage and bed, respectively, while roller4 is journalled on a stub shaft 5 (held to a sheet metal bar 6 at apoint substantially midway the ends of the carriage) and travels on theupper edge of a second sheet metal bar or rail 8,. Bar 6 is detachablyheld againstthe rear edge' of the carriage base plate lby screws 7, andbar 8 is detachably held against the rear edge of bed 28 by screws 9.

The platen carriage 27 supports platen 18 above and in rear of the typebar pivots, and the lcarriage and its bed 28 overlie the space betweenframe wallsll and 13 while guide members 29 and 31 arelocatedsubstantially entirely inthe space between said walls and Vtheconnecting portions of side walls 1,2.

Members 29 and 31 are @provided 'with .cooperating` races 32 and 32a,respectively, in which travel ball bearings 32, said members,

racesV and bearing balls being arranged to guide the shift frame toshift in a planeparalf lel with the planes of wall 13 and segment 14.The shift frame is shiftable upward and rearward from lower to uppercase position by either offtwo shift key levers 33 having forked rearends embracing studs34v on the forward ends of side arms 35 of a shifttorsion `framecomprising saidarms and a rock shaft 36 to which the armsare held. Shaft 36 is `rest 40 lfor the headsof the type'bars.

13 and are fulcrumed on transverse pivot` screws 38 held to apair ofbrackets 39 (secured to frame walls 12), which brackets also support arcurved and rearwardly inclinled T ie lower case position of the shiftframe is determined by engagement of stops 41 on members 29 with stopscrews 42 on a pairz of brackets 43 held to frame walls 12, while theupper case position of the shift frame is determined by engagement ofstop screws44 on members 29 with stops 45 on brackets 43. The foregoingparts are all constructed and arranged as inthe machine and applicationabove referredV to. l l

In the improved machine, herein shown, frame 35-36 is arranged tocounter-balance the shift frame by connecting lugs 46 on arms 35 withar1ns48 on brackets 43 yby a pair of counterbalancing springs 47. ,Thepresent machine is providedk with ribbon vibrating, ribbon feeding, andribbon reversing means (not shown)V all mounted to shift with the shiftframe, and all operated from an aet-uator comprising a rock shaft 64.The construction and mounting of the ribbon mechanism, andthe mode ofoperation thereof from said rock shaft, aredisclosed in the applicationof Avery, Petermann and Harmon, Serial No. 148,255, filedNovember 13,1926.

The ribbon mechanism actuator or rock shaft 64 is journalled on themain. frame and extendsrtransversely of the machine under the lower edgeof wall 1,3 above the .key levers 19. Said actuator L64 is operable,together `with an actuator 166 for the dog rocker of the escapementmechanisnnfroma singletypebar-actuated universal bar 49, and the dogrocker of the` escapement is operable indey pendentlyy of said universalbar and actuators 166 and 64 by an actuator 178operated by the space bar167 of the machine.

The arcuate sheet metal universal bar 49 is located between wall 13 andsegment 14 and vibrates in a recessl in the segment, said universal barlying in a plane parallelwith f The side arms extend rear-' ist ' 11andthe base line of the main frame.y

vided with openings 52 and 53 for the arm sections 50 and 51. The frontportions of arm sections 50l and 51a are rigidly but detachably held tothe right hand side faces of the rear portions of sections o() and 51,in rear of wall 13 and plate 21, by pairs of clamping screws 54 threadedinto sections 5() and 51.

The side arms extend rearward and downyward through the shift frame andshift torsion frame, between the guides 29 and between the rock arms 35,and between the bed 28 and brace rod 30, to a point adjacent wall See.tions 5()a and 51"L of the side arms are offset laterally inward at the4rear ends of sections 50 and 51 and are provided with longitudinal slots50b and 51b in their offset rear portions extending perpendicular to theplanes of wall 13 and segment 14. These slots are open at their rearends and correspond in width with the diameter of vrock shaft 36, whichshaft extends through said slots to form a support cooperating with theslots to guide the universal bar side arms to reciprocateend-A wise. Atransverse bridge or spacer bar 55, formed integrally with section 50'Lforward of shaft 36, abuts the inner face of section 51a; The side armsare supported and guided intermediate the universal bar 49 and shaft 36on fore-and-aft rockable supporting arms 56v and 57 which are rigidlyheld at their lower` ends to a. short transverse rock `shaft 58. Shaft58 has trunnions 58fL journalled on the inner ends'of horizontal bearingscrews 59 threaded through the rear ends of a pair of arms 21a and 21bwhich are formed integrally with fulcrum plate 21 and extend rearwardand downward to a point forward of rod 30 and close to the base line ofthe `main frame.

Arms 56 and 57 extend upward andl rear-y ward, forward of rod 30, at aslightly less angle from the vertical than wall 13 and the shift frame,and have pivot holes in their up-4 per ends in which are engaged thereduced inner ends of pivot 'studs 61, the reduced outer ends of thestuds being swaged in aper# tures in the side arm sections 50 and 51,reV spectively, forward of side arm sections 50LL and 51a.

Forward movement of the universal bar 49 is limited by engagement ofsaid bar with the.

adjacent their pivots with lugs 17 a forengaging the front edge of theuniversal' bar and moving the universal' bar rearward, and being rockarms 56 and 57 are such that pivot studs Y 61 swing between pointssubstantially yequal distances at opposite sides of a plane through theaxis of shaft 53 parallel with wall 13.

ylie described arrangement and movement of arms 56 and 57, together withthe described arrangement of slots 50b and 51b in the side arms and ofshaft 36, provides for supporting and guiding universal bar 49 tovibrate obliquely to the horizontal plane of the machine in a pathsubstantially perpendicular to the inclined plane of the segment 14 andits type bar pivot wire 16. u c

A rock arm 68 depends from the ribbon mechanism actuating shaft 64 at apoint sub-` stantially in the fore-and-aft vertical plane of sidearni`51.--51a of universal bar 49. This rock arm extends down betweenadjacent key levers of the machine to a point below the key llevers andclose tothe base line of the main to, and-yieldably held in, normal'position by a.y return spring 74. Spring 74 is connected at its rear endwith a rock arm 73 depending from shaft 64 and is ,connected at itsforward endrwith a spring anchor bar 75.

This anchor bar extends transversely of the machine and is supported atits ends in slotsv 76 in arms43fL of brackets 43, said bracket armsextending forward under wall13 and supporting bar 75 below the keylevers 19 and forward of the rear upturned end portions of the keylevers.. Return springs 7 7 for key levers 19 are connected at theirrearends with the key. levers and attheir foi'- ward ends with the bar 7 5.

rThe actuator 166 forthe escapement dog rocker comprises a shoe ortappet formed,-

on the rear end ofside arm section 50 and projecting rearward beyond therear end of the outwardly `offset forward portion of side arm section50'L1 of the universal-barfcarrying means., The rear contact edge ofsaidtappetor shoe'166 inclines upward and rearward in l a plane parallelwith'wall 13 and the path of case-shift movement of the shift frame andsufficiently long'to actuate the dog rocker f bon mechanism and theuniversal bar, the following means are provided. Space bar 167 issupported forward of the character' keys on the forward ends of a pairof sheet metal rock arms 168 which are fixed at their rear ends on atransverse rock shaft 169 having trunnions 170 at its ends 'journalledin forwardly extending ears 171 punched up from the comb member 22. Arock arm 17 2 fixed on said shaft` extends downward and forward in frontof the comb 22 and is pivotally connectedat its lower end with the frontend of a fore-and-aft exte 'ng tappet bar 174i by a transverse pivot sciew 173. Tappet bar 17st extends rearwardlythrough a guide slot 175 incomb 22 and then under sub-lever segment 24;, rock shaft 6a andwall 18.Said bar extends upward behind wall 13 and then diagonally rearward anddownward along the outer side of side arm section 50 of the vibratorysupporting means for universal bar49. Thisinclined rear portion of thebar 17d is formed with a guide slot 176 extending substantiallyperpendicular to wall 13 and in which. is engaged the reduced shankportion 177'LL of a supporting and guiding stud 177 held to, andextending horizontally outward from the upper part of rock arm 56 onshaft 58. rlhe independent actuator 178 for the dog rocker comprises atappet or shoe formed on the rear end of bar 17d and located alongw sideof tappet 166. The rear Contact edge of tappet 178 is parallel with wall18 and the path of case-shift movement of the shift frame and is madesuiliciently long to actuate the dog rocker in both case positions ofthe shift frame. Tappet 166 is preferably arranged slightly forward oftappet 178 so that the dog rocker may be actuated by a short dip ofthcspace bar andthe dog rocker will be rocked and may return to normalposition during a minimum final part of the printing stroke and initialpart of the return stroke of -a type bar. This arrangement also providesfor utilizing the full throw of the universal Vbar to actuate the ribbonmechanism.

Bar 1711 and space bar 167 are returned, and normallyyieldably held inthe position shown in the drawings, by a coil spring 179 which isconnected at its rear end with bar 174 and at its forward end' withanchor bar 7 5. An upstanding stop lug 180, formed on bar 17 1, engagesthe rear face of comb 22 to limit return movement of bar 17dA and thespacebar Depression of the space bar and rearward movement cf'tappet bar1711 are limited by engagementof stop lugs 181 on thespacebar-supporting arms 168 with the upper ends of the forward pair ofthe four rubber supporting feet 182 which are attached to the Vmainframe,'as in the Corona Four machine and as disclosed in saidapplication of Ely and Harmon above referred to.

With the above described arrangement, theV tappet bar 17 4l (whilesupported `and for the universal bar.

lower end of the bushing.v

guidedv in part on a swinging part of the supporting and guiding meansfor universal bar 4.9) is operable without moving the universal bar orthe ribbon actuator, and the universl bar is operable withoutactuatingthe tappet bar. stud 177 and slot 176, support and guide bar 17 4f sothat tappet 178 moves rearward and downward, when the space bar isdepressed, with its contact edge always substantially parallel with wall13 and the path of shift of the shift frame, the pivot 173 movingrearward and downward and slot 176 extending rearward and downward.

A sheet metal 4dogrocker-supporting bracket 80 has its relatively shortand narrowrtiat main kbody part detachably heldl against the bottom faceof the carriage bed 28, substantially midway the ends of the bed, amilis formed with' a pair of integral side arms 81 and 82 bent down at theends ofthe bracket and extending rearward and downward parallel witheach other to points be- -yond the rear edges of the body of the bracketand the carriage bed and within the main frame above rock shaft 86. Thearms 81 and 82 lie flatwise in fore-and-aft extendingven tical planesand do not extend down within the vibratory supporting and guiding meansA steelbearing bushing 83 extends through a central aperture 8d in thebody part of bracket 80 perpendicular to said body part and the carriagebed, and has an intermediate circumferential shoulder portion 83-thereof swaged tightly in said aperture, so that when the bushing-isonce assembled on the bracket it becomes in effect a permanent part ofthe'bracket.

A feed pinion 85 is formed integrally with a pinion shaft 86 atthe-upper yend of the shaft. Shaft 86 extends through and is journalledin bushing' 83, and is formed with a circumferential collar 86a belowthe feed pinion seated on the upper end of the bushing. The shaft isformed with a threaded axial bore 87 in its lower portion andtheprojecting lower end of shaft 86 below bushing 88 is cut away atdiametrically opposite points to form two integral diametricallyopposite key portions 861? extending outward from said bore and engagedin correspondingly arranged radial notches or slots 88L at oppositesides of a central aperture 88 in a toothed sheet metal escapement wheel89. Saidkeys and notches are so arranged with relation to the teeth ofthe feed pinion and esce-pement wheel, respectively, that when the wheelis seated on the reduced end ofthe pinion shaft the teeth of thewhe-elfand pinion will be in proper relationwith. each other.` The wheelcorresponds in thickness with the length of the projecting lower end ofshaft 86 sol that its upper face looselyengages the A retaining screw90is passed upward .through a washer Rocker arms 17 2 and 56, and

and the'lower end of lshaft 86) and the central aperture in wheel 89 andis screwed into the threaded bore 87 in the shaft 86. It will beobserved,thatfcollar'86a and the top face of wheel 89y cooperate withtheends of bushing 83 to prevent vertical'iplayfof the feed pinion and itsshaft and the escapement wheel, and thatfthe feed pinion-and its shaftand the escapem'ent wheel may be readily assembled on the bracket andreadily removed therefrom.l The y feed pinion, when the bracket-isattached 4to the hed' 28 by the pair of 'screws v92 (which are passedthrough holes 80a in bracket 80.and are screwed upward into threadedapertures 92a. in the bed located at predetermined points) meshes withav feed rack 93 on the carriage 27 and is located between the carriagebed and the base plate of the carriage. This feed rack com- )rises anintegral-'Hangs extending. upward land forward from the lower edge ofthe soy bearing-rollerecarrying bar 6, before described, between thebase plate of the carriage 27 and the carriage bed 28, parallel with thebed, and formed with teeth along its forward edge.. The carriage bed isprovided with an opening94 through which theupper end of bushing 83extends and through which the lfeedpinion is adapted to pass in assem#Vbling and disassembling the escapement.

A dog rocker, together with a pair of dogs and controlling means for thedog rocker and for the pivoted or feeding dog, are also adapted to beassembled on bracket 80,.and

these parts adjusted to properly coacty with escapement wheel' 89,before the bracket is attached to the bed. The dog rocker 95 is formedof sheet metal and its main body part rtheir'rear ends with conoid'albearing aper tures 98. A pair of horizontally disposed bearing' screws99v are screwed inward through threaded apertures 100 in the rear endsof the bracket arms 81 an'di82 and have conoidal bearing `porti-'ons 99aengaged inapertures 98 in thefdog rocker pivot ears,fso

that the-.dog rocker maybe adjusted trans-v versely of the machinel andheld in adjusted position by means ofthe bearing screws 99 to vary .therelation between the rigid or lholding dog 101 and the esctpementvwheel' 89. Lock nuts are preferably provided for hold.-

'ing the screws 99 in adjusted position, as

shown.

Dog 101 is formed integrally with the main body part of the dog rocker95 and projects forward flatwise from the forward edge of said body partwith its rstraight vwheel-tooth holding or right-hand edge 101*iextending fore-and-aft of the machine substantially on `a line throughtheaxial line ofthe escapement wheel, and said'dog is permanentlyben-dable up'V and downk for purposes of adjustment, being shownoffsetupwardly slightly relatively to thefrockerin the drawings. The pivotedIor feeding dog 102 is lformed of sheet metal and is pivotally heldintermediate its forward and'rear ends to 'the dog rocker by a pivotscrew'V 103 passed 4left-hand ed ge102b. v `The rearwardlyextending tailportion 102C ofthe dog inrear of .the dog pivot, togetherwith rarms 105and 106, wipe over thebottom face of the dog rocker and afforda broadanti-tilting bearing Jfor the dog .without anundesirableamount offriction.A f, Y 1 Y v A pair of control devices 107v and 108 for thefeeding dog` co-operate with the dog arms 105 and 106. Each of`r thesedevices consists of a three-armedvsheet metal lever, and said devices-107 and 108 are held to the main body part of the dog rocker bypivotscrews u109 andi110 located at'opposite sides of the dogy pivotand'slightly in rear of a plane extending transversely of the-machinethrough said t dog pivot. The pivotlscrewv of each device passesupwardthrough a bearingaperture in the device-at the j unctionof thethree arms, said screws 109 and 110 being screwed .at their upper endsSinto threaded holes 111 and 112 in the dog rocker and holding said de?vices to the under face of the dog rocker to swing in a plane parallelwith the plane of the flat body part of said rocker.

The rearwardly extending arms 107a and 108"l of said devices are formedwith pendent lugs at their rear ends to which are e011-,

- nectedthe opposite lends of a helical tension spring 113 of suchlength that said spring Ais prisin'g arcuate metal strips punched downfrom the liat body part ofthe dog rocker and integral therewith at theirinner and. outer ends, the stops being located adjacent opposite ends ofthe dog rocker. `When the loose dog is'l free from the escapement .wheelV89,

spring 113 normally holds the forward edges ofthe inwardly extendingarms107c and iso ' 108 .of the'controller flat against-"the rear ldiateposition by the teeth of the vescapevthe path of dog arm 105.

- the dog.

edges of the dog arms105 and 106, respectively, and the arms 107b and108b in engagement with `stops 114 and 115, toyieldably "maintain thef-eedingfdog in an intermediate position (shown in Fig. 11) from whichit :may be rocked 'in either direction by a tooth vof said wheel.

The feeding dogis adapted to be rocked 'toward the left from itsnormalintermedivate-,position by the teeth of the escapement wheel on returnmovements of the dog rocker, after engagement of the holding or straightYradial edge 89'd of one of said wheel' teeth -with the holding edge102a of the dog, against the resistance of spring 113 applied to thevdog through controller 108 which will rock in 'counterclockwisedirection away from stop 115 until the arm 105 of the dog engages`behind va stop 116 on the dog rocker, while rcontroller 107 will beheld stationary against :stop v114. Stop 116 comprises a transverselyextending linger formed integrally with the ment wheel upon reverserotation ofthe wheel, as shown in Fig. 13,v suoli reverse rotationoccurring during carriage-returning and back-spacing operations, and thebeveled edges 89b of the wheel teeth cooperating with the beveled edge102b of the dog to cam the Vdog intermittently toward the right topermit the wheel teeth to freely pass the dog.

AUpon such reverse movement of the wheel, controller 108 will be heldagainst stop 115 and controller 107 will vibrate from and to its stop114 as each tooth of the wheel passes The platen carriage 27 is normallyurged from right to left by a spring drum 117 located under the carriagebed and rotatably held thereto at 118, a draw band or cable 119, `woundon and attached to the drum at one end, passing over a pulley 120journalled `in a slot 121 in the carriage bed and being attached at itsother end to a screw122 held to the right hand end portion ofthefcarriage bed plate. The drum spring normally tends to drive theescapement wheel in the directionv indicated by the arrow in Figs. 9 and11 through the medium of the feed rack and pinion.

" A dog rocker return spring 123 is connected at its rear end with theouter end and forwardly extending stop arm 126k f.

(formed integrally with dog rocker pivot ear 97 and located abovethevibrat-ory supporting means for the universal bar) nor- VVmally engagesaty its forward end the bottom face of bracket to arrest return movementof the rocker with the feeding dog 102 f in the plane of the escapementwheel, said dog normally holding the carriage against the pull of thespring drum and cable by reason of the engagement of its holding edge.

102a with the straight radial edge `89a of one y of theteeth of theescapement wheel 89, as

most clearly shown in Figs; 5 and 9.

Anv integral arm 127 extendsy downward and forward from the dog r-ockerpivot ear 97, at the out-er sideof the inwardly offset rear portion ofthe section 50a of the left hand side arm of the universal bar forwardof shaft 36, and isprovided at its lower end withan outwardly extendingcontact lug 128 normally lying flatwise in a plane perpendicular to wall13 and the path of'movement of the shift frame andextending behind the`lower portions of the rear contact edges of tappets 166 and 178. As thecontact edge of each tappet is parallel with the path of shift oftheshift frame and ismade long enough to engage the narrow forward edge ofcontact lug 128 in bothy case positions of the shift frame, it will beobvious that each tappet will rock the dog rocker uniformly in both casepositions ofthe shift frame.

As shown, tappet 166 is located slightly lforward of tappet 178 whichnormally engages, or substantially engages, with the contact lug. Bythis arrangement the escapement may be tripped by a short dip of thespace bar 167, and universal bar 49will move the ribon actuatorthroughout its rearward travel and will trip the dog rocker during thelast part of its rearward travel, thereby rendering proper action of theribbon-'mechanismv (and particularly the ribbon rvibrating means) morecertain, and providing for speedy action of the escapement during asmall final part of theprinting stroke and a corresponding initial partof the return stroke of a type bar, and also contributing to easyoperation ofthe keysv by providing for successively starting operationof the type bar, the ribbon mechanism, and the escape- `mentmechanismduring the down stroke of a character key.

y le5 either inward over stop arm '126 forward of the body part ofthedog rocker and then under an integral stop lug 130 projecting forwardfrom the body of the ldog rocker at the left of the lholding dog 101. Ahorizontally and Vtransversely extending` shouldered pivot screw 131extends inward through and isV journalled in a bea-ring hole 132 formedin theforward end of bracket arm 82, and the reduced threaded inner endofsaid screw ris threaded vin a screw-threaded hole 133 in the forwardend of the lever arm 129. The second Varm 134 of the bell-crank leverextends upward and lrearward from the forward end of arm 129 through afore-and-aft vextending slot 135 in the carriage bed 28 into the spacebetween the carriage bed and the base plate `of thecarriage. A spring136 extends downward and rearward from a lug 137 formed on thebell-crank lever forward of the pivot of the lever to a lug 138 formedon bracket arm 82. Spring 136 normally holds bell-crank lever 129-134 inthe position shown in Figs. 1, 5, 7, 9, 10, 15 and y17 in which anupstanding stop lug 139 on lever arm 129 (in rear of the lever pivot)engages the bottom face 'of bracket 80 alongside the forwardend of stoparm 126, with the lower edge ofextension 129 of lever arm 129 spacedabove stop arm 126. and with the upper edge of said extension 129"Lspaced below stop lug 130 on the dog rocker. Extension 1291 forms aspring-held stop ar ranged to be engagedby lug 130 to quietly arrest theforward and downward tripping movement of the dog rocker when theholding dog 101 has moved down into the plane of the .escapement wheel89, as shown in Figs. 7, 11, and 12, engagement of lug 130 withextension 129a taking place when the dog 101 is in position to catch andhold the wheel tooth from which dog 102 has just been released and whilestop 139 on lever arm 129 still remains engaged with bracket 80. `Stoplug 130 is bendable up and down for purposes of adjustment.

Provision has been made for releasing the carriage by hand for runningmovement in direction. The carriage releasing means comprises thebell-crank 129-134 and a sheet metal bail140, the cross-bar of whichextends between the base plate of the car.-

riage and the carriage bed in front of arm 134 of the bell-crank. 5 Theside arms of the bail 140 extend upward at the ends of the carriagebehind the platen' shaft'18a and are pivoted f on horizontal pivotscrews 141 threaded-into the end plates of the carriage intermediate theends of said side arms. The side arms are formed with fingerv pieces1402l at their upper ends projecting above the platen shaft. The bailisnormally heldin the position shown in Figs. 1, 5, and 7 by thespring-returned bell-crank 129-1134. Upon forward 'rocking ofthe lingerpie'cesf140a by the operator until arrested by stop studs 142 (held toand projecting outward from the carriage end plates),the bail andbell-`V crank 129-134 move to the position shown in Fig. 8, wherein thestop `arm 126 on the dog rocker has been engaged by bell-crank extension129? and depressed suflicientlyto rock the dog rocker forward anddownward from normal position and efar enough past the position shown in`Figs. 7, 1l and 12 to carry both escapement dogs down below the, planeof the wheel, which is thus completely freed from the dogs so that lthecarriage may be freely run toward the left, and

whereby the carriage may be also run toward the right (if desired),without the ratching action of dog 102 shown in F ig. 13v andhereinbefore described. 'Upon release of the linger pieces, the '.bail',bell-crank and .dog rocker will be returned to'normal posi tion by thesprings 123 and 136, and dog 102 .will engage one of the teeth of.wheel89 and hold the carriage in its adjusted position'.

Simple Vmeans has been provided co-opera` tive with the forward feedingmeans above described to effect step-by-stepbackward feeding of thecarriage, in .either case position of the shift frame, from a backspacekey located in the'keyboard of the machine. The back-spacing dog 143isformed on, andextends rearwardly from, the left hand end of a sheetmetal clog-carrying bar 144 at the right of the feed pinion. The dogcarrier 144Ylies`flatwise between the carriage base plate and thecarriage bed and extends toward the right from dog 143 Ato a point infront of an opening 145 formed in the carriage bed adjacent the righthand end of the bed. A screw 146 Vextends down through a longitudinalslot 147 in the middle portion of the dog carrier and is threaded intothe cardog carrier on the upper face of the carriage riage bed 28 toslidably and rockably hold the bed. A dog carrier return spring 148,'connected at its inner endwith an integral lug 149 formed on the righthand end of bracket 80, and connected atvits right hand end with anintegral lug 150 extending rearward from carrier 144 at a point totherigh-t of slot 147 andthen downward througha longitudinal slot 151 inthecarriage bed to therear of the forward edge of said slot 151, normallyholds the dog carrier in the position shown in Fig.r 6, wherein thescrew is engag-:d against the outer end of slot 147 and dog'143 isrocked forwardfout of feed rack 93. The spring 148 extends slightlyrearward from lug'149 to lug 150 and normally slides the carrier inward,and rocks its dog carrying end forward and itsouter end rearward againstan upstanding lug 152 formed on the rear endv of the rearwardlyextending` arm ofv a bellcrank lever 153. Lever 153 is pivotally held tothe under face ofthe carriage bed (by a pivot screw 154 threaded upwardinto Asaid bed). to rock in a plane parallelwith the plane of the bed,and lug 152 extends up through the openingy 145 -in the bed att-helefthand end of a lug 155 projecting rearward from the outer'end of thedog carrier. Lug 155 is formed at its left side with a rearwardly andoutwardly extending cam edge 155ZL terminating in a fore-and-aftextending shoulder 155?7 and the lug has a fore-and-aft exi tending stopcdge'155c'at its right side normallyspaced toward the left from an up-Standing stop lug 156 formed on one of the ribbon'mechanism supportingbrackets 157 of the machine. Bracket 157 is fastened to the under faceof the carriage bed by screws', of which screw 154 is one, and lug 156projects up through opening 145 into the path of .movement of edge 1755Cof lug 155A on the dog carrier 144. y Y Lever 153 has its second armextending outward from its pivot and connected with the rear end of alink 158 which in turn is con- Ynected at its forward end with theupwardly and rearwardly extending arm of a bellcrank back-space keylever 159. The key-carrying army of the back-space key lever extendsforward from the pivot of the lever through one of the guide slots ofthe comb 22 and supports the backspace key at the right hand side of thekeyboard. rllhis key lever is fulcrumed on a horizontal pivot screw 160passing outward through the lever at the junction of its two arms andthreaded into the right 1 f from the key lever and is adapted to swingabout its connection with the key lever upon an upper case movement ofthe shift frame, the rear Vend of the link moving from a point below aplane through said point of connection and perpendicular to the path ofcase shift movement of the frame to a point substantially the samedistance above said plane7 ward the right to draw thelcarriage backwardor to the right until the tooth next in advance of the held tooth ofescapement wheel'89 has cammed past the op'positely tiltable feeding dog102 inthe manner shown in Fig.13. As soon as the tooth in advance of thepreviouslyhcld tooth clears dog 102, said dog snaps into its normal`intermediate Vposition and stop edge 155C of lug 155 abuts stop lug 156onk bracket 157 and prevents further movement of the back-'spacingmeans. Upon release of the back space key, the back'space key lever anddog return to normal position and escapement wheel tooth which has beencammed back past dog 102 advances and enga'gesedge` 102 of the dog, asthe carriage moves slightly tqward the left again under the pull of thespring drum, and rocks said dog` in the opposite direction tocarriage-arresting position with its arm 105 engaged with stop 116, andthe carriage is then held in a position one letter-space farther towardthe right than that oceupiedrbefore depression of the. back space key.

1t will be observed that an efficient escapement n'iechanism has beenprovided wherein the feedingdog is adapted to rock in oppositedirections from a normal intermediate position and is controlled bymeans insuring quick, positive and quietaction of the dog; that acompact assembly of rotary escapement and type-bar-operated universalbar inechanismv and space bar mechanism for actuating the same isprovided wherein the escapeinent mechanism is located ,above and outsideof the universal bar mechanismand space bar mechanism; that a simpleescapement releasing means is provided; that means are provided forprewntinnl voverthrow of the dog rocker upon actuation of a characterkey or the space bar; that simple feed means has been provided foradvancing and retracting the carriage; and that the entire escapementmechanism except the feed rack and spring drum and cable is assembled ona single bracket and may be readily attached and removed with thebracket as a unit.

As hereinbefore described, the provision of tail piece 102C on thepivoted feeding dog gives the dog an antitilting wiping engagement withthe bottom face of the dog rocker at both sides of its bearing on theshouldered pivot screw 103; f The reduced threaded portion of the screw,which is threadedy through the screw hole 104 in the dog rocker at alltimes, thus preventing wabbling of the` dogon its pivot, andmaintainingthe nose of the pivoted feeding dog in the proper plane withrespect to the'ixed dog 101 at all times In order toprevent possibleoverthrow of the carriage in back-spacing, due to momentum acquired bythe carriage upon a rapid or violent depression of the back space key,a`

rearwardly facing shoulder 1551 is provided on the back space dogcarrier 144, which shoulder engages behind stop lug 15,6 at the end ofthe down stroke of said key as stop edge 155y engages said stop lug 156.lt will be seen that this arrangement will preventl that tooth of rack93 which' follows. the tooth engaged by the back space dogv 1113 fromcamming thedog out of t'herack at the end of the movement of thedogcarrier by the back space key when the carriagel is jerked Vviolentlytoward the right.

ldhat we claimisy: Y j 1. 1n a typewritingmachine, the' eomb1 nation ofa power-driven platen carriage', a

toothed escapementwheel, a holding dog, a

pivoted feeding. dog sliiftable in opposite directions about its pivotfro'ma normal 1ntermediate position by the teeth of said wheel,

a pair of pivoted controllers for said dog en-"fv gageable therewithvat" oppositeisi'des of the pivot of the dog, and a single tensionspring connecting said controllers and normally urging the controllersin `.opposite directions about their pivots against the dog'to yield-'ably hold the dog in its normal intermediate position. Y

2. ln a typewriting machine, the combina.- tion of a power--drivenplaten carriage, a toothed escapement wheel, a holding dog, a pivotedfeeding dog shiftable in opposite directions about its pivot from anormal intermediate position by the teeth of said wheel, a pair ofpivoted controllers forV said dog engageable therewith at opposite.sides of the pivot of the dog, a single tension spring connecting saidcontrollers and normally urging the controllers in opposite directionsabout their pivots against the dog to yieldably hold the dog initsnormal intermediate v position, and a pair of stops engaged Yby saidcontrollers when the feeding dog is in its in termediate position'andarranged to limitY swinging movements of the controllers under the pullof said tensionspring.

-. 1n al typewriting machine, theA combination of a. power-drivencarriage, Va toothed rotary escapement wheel geared tosaidyoffi?" riage,a dog rockerpivoted to rock about an axis perpendicular. to the axis ofrotation of said wheel, a feeding dog shiftably mounted on said dogroel-:er for movement in opposite directions by the teeth of saidwheel,a pairof controllers for said feeding dog shiftably mounted on saidv dogrocker, a single tension 'spring connecting said controllers and urgingthe same in opposite directions, said controllers being arranged toexert opposing' thrusts on the feedingv dog under the pull of saidspringl to normally yieldably hold the feeding dog in an' intermediatepol sition, and a holding dog rigidly mounted on 'the dog rocker;

l. ln a typewriting machine,vthe combination of a power driven carriage,a toothed rotary escapement wheel geared to said carriage, a dog rockerlpivoted to rock about an axis perpendicular to the axis of rotation ofsaid wheel, a feeding dog shiftably mounted on said dog rocker formovement in opposite directions by the teeth of said vWheeha'pair ofcontrollers for said feeding dog shiftably mounted on said dog rocker, asingle tension spring connecting said controllersand'urgthe same inopposite directions, said con-V trollers beingar'ranged to exertopposing thrusts on the feeding "dog under the pull of said spring tonormally 'yieldablyhold the feeding dog in an intermediate position,a

holding dog rigidly mounted on the dog rocker, means fornormallyyieldably holding the dog rocker in a. position in which the feeding dogis engaged witha tooth of the wheel, and character key-operated meansfor rocking the dog` rocker about its pivot to releasethe feed- Alng dogand' bring the holding dog into engagement'with a `wheel tooth to holdthe wheel duringmovement of the feeding dog to its normal intermediateposition.

5. In a typewriting machine, an'escapement` mechanism comprising anescapement of occupying three different positions, and

single tension spring and arranged to coact with the feeding dog tonormallyjmaintain said dog in its intermediate position. v

Gfln artypewrting machine,-an lescape` ment mechanism; oomprisingranescapement wheel, aholding dog, a feeding dog capable of occupying threed'ierent positions, a pair of pivoted controllers connected by a singletension spring and arranged to coact with the feeding dog to normallymainta'infsaid dog. in its intermediate position, means for limitingpivotal movements of saidcontroh 1ers under the lpull of said spring,and means for positively arresting the feeding dog in one of-its endpositions. f Y .7. 1n an escapement mechanism,a. toothed escapementwheel, a vibratable dog carrier, a-

holdinfr dos r on said carrier a feeding do@ b c: 7 n, b

wheel, a holding` dog, a feeding dog capable y Csi teeth of said wheelto either side of a central normal position, a pair of controllerspivoted on said carrier to abut and exert opposing site directions abouttheir pivots into contact with said dog to normally hold the dogyieldably in its central position.

8. In an escape-ment mechanism, a toothed escapement wheel, a vibratabledog Carrier, a holdingdog on 'said carrier, a feeding dog pivotally heldto said carrier for rocking tlier'eof'by teeth of said wheel in oppositedirections from a normal central position, a stop on the carrierengageable by the feeding dog for arresting swinging of the dog in onedirection while still engaged by a tooth of said wheel, a pair ofVpivoted controllers mounted on said carrier engageable with they:feeding dog at opposite sides of its pivot, a tension spring`connected at its ends with said controllers to rock the same in oppositedirectionsabout their pivots into engagement with the feedingdog, andmeans on the carrier for holding each controller stationaryv uponmovement of the other controller against the pull of said spring by thedog upon swinging of the dog out of its central position by aneseapement wheel tooth, said meansA being arranged to permit engagementof both controllers with ther dog Awhile the dog is in central position.

9. In an escapement mechanism, a rotary toothed escapement wheel, meansnormally urging said wheel to rotate in one direction, a vibratable dogcarrier, a holding dog on saidA carrier, a feedingdogpivoted on saidcarrier for movement to opposite sides of a central normal position byteeth of said wheel, said feeding dog having a pair of arms extending inopposite directions from its pivot, a pair of levers pivoted on said dogcarrier on axes parallel with the pivotal axis of the feeding dog andlocated at opposite sides of the feeding dog pivot, said levers havinginwardly extending a-rms cooperative with the outwardly extending armsof the feeding dog to rock the dog in opposite directions and arms at anangle to Said inwardly extending arms, a tension spring connecting thelatter arms of the levers to roel; the respective levers in a directionto cause the inwardly extending lever arms to normally contact with thefeeding dog arms and yiel-dably hold the feeding dog in centralposition, and stop means on the carrier cooperating with the levers toholdone lever stationary Aagainst the pull of said spring when t-heother lever is rocked against the pull ofthe spring by a swingingmovement of the dog from its central position.

10. In'an escapement mechanism, a rotary toothed escapeinent wheel,means normally urging said wheel to rotate in one direction, avibratable dog carrier, a holding dog on said carrier, a feeding dogpivoted on said carrier ,for movement to opposite sides vof a 'centralnormal position byteeth of said wheel, said feeding dog having a pair ofarm extending A Astops being arranged to permit the armsof the feedingdog to engage said inwardly extending lever arms when the dog is incentral position, and said inwardly extending lever arms engagingcorresponding edges of the dog arms so as to offer opposing resistanceto movement of the dog from central position.

l1. In an escapement mechanism, a vibratory dog carrier, a rigid holdingdog on said carrier, a pivoted feeding dog on said carrier, a toothedmember normally urged in one vdirection and movable in the oppositedirection, means for .vibrating the carrierto position the dogs forengagement alternately with teeth of said member, afpair vof pivoteddevices engageable bythe pivoted dog to normally yieldably hold the dogin an intermediateposition from which itis movable in oppositedirections against the resistance of different ones of said devices'byteeth of said memberin accordance with the directionof movement of themember, stopping means for determining t-he normal position of saiddevices, and spring means urging said devices about their pivots tovnormal position.`

12. In an escapement mechanism, a. vi.- bratory dog carrier, arigid'holding dog on said carrier, a pivoted feeding dog on saidcarrier, a toothed member normally urged in one direction and movable inthe opposite direction, means for vibrating the carrier to position the'dogs forA engagement alternately with teeth of said member, apairofpivoted devices engageable by the pivoted dogtov normally yieldablyhold the dog in an intermediate position from which it is movable inopposite directions against the resistance of different oiies of saiddevices by teeth of said member in accordance with the direction of`movement of the member, stopping means on Athe carrier for arrestingpivotalmovement of Vnormal position, and stopping means on the dogcarrier for arresting pivotal movement of lthe feeding dog from itsnormal intermediate position by a. tooth of the toothed member duringmovement of said member in normal lll() direct-ion While said dog isstill engaged by said tooth.

13. In an escapement mechanism, a vibratory dog carrier, a rigidholdingV dog on said carriage, a'pivoted feeding dog on said carrier, atoothed member normally urged in one direction and movable in theopposite direction, means for vibrating the 'carrier to position thedogs for engagement alternatelyy means on the dogl carrier for arrestingpivotal movement of the feeding dog from its normal intermediateposition by a tooth of the toothed member during movement of said memberin normal direction While said dog is still engaged by said tootln'andkeyoperated back-spacing means for driving said ltoothed member inreversedirection.

14.' in a typewriting machine, a Vreciprocable platen carriagespring-driven in vone direction, a toothedmember ino-vable in oppositedirections byreciprocatory movements of the carriage,a vibratory dogcarrier, a

holding` dog rigidly mounted on the carrier, a feeding dog pivotallymounted on the carlrier for swinging movement to opposite sides o-f anormal central position by teeth of said member, means connected Withthe 'carrier for normally holdingthe carrier in position for engagementof the feeding. dog With a tooth of said member, character-key-operatedmeans for shifting said lcarrier to position the holding dog forengagementwith aftootli of said member and freeing the feeding dog, apair of devices pivotally mounted on the carrier for engagement-thereofbythe feeding dog, stopping means on the carrier vfor determining thenormal position of said devices, said devices When in normal positionbeing engaged ivith the dog to resist movement of thevdog in bothdirections fromits normal central position, spring means constantlyurging said devices about their pivots toward said stopping means, andmeans for positively arresting pivotal movement of the feed dog fromcentral .position bya tooth of sa id member While said dog and tooth arestill engaged upon an advancing'movement ofthe carriage by its drivingspring;V

l5. In a typewriting4 machine, a reciprocable platen carriageVspring-driven in one direction, a toothed member movable infoppositedirections by reciprocatory movements of the `carriage a'vibratory dogcarrier, a holding dog rigidly mounted on the carrier, a feeding dogpivotally mounted on-the carrier for swinging movement to opposite sidesof anormal-central position by'teeth of said member, means connectedWith the carrier for normally holding-the carrier in position forengagement of the feeding dog With a tooth of said member,`character-key-operated lmeans for shifting said carrier to position theholding dog for engagement With a tooth-of said member and freeing thefeeding dog, a pair of devices pivotallymounted onthe carrier forengagement thereof bythe feeding dog, stopping lmeans'on the carrier forvdetermining the normal position of said devices, said devices `when in.normal positionk being engaged With the .dog to resist movement of thedog in both directions fromits normal central position,springmeansvconstantly urging said devices -about their pivots tovvardsaid stopping means, means for positively arresting pivotal movement ofthe, feed dog from centrall position by a tooth` of saidmember Whilesaid dog and tooth are still engaged upon an advancing movement ofA thecarriage by its driving spring,

and key-operated vback-s'pacingv means for shifting the carriage` inopposition toits driving spring a distance sufficient tol force Vthetooth of said member next inadvanceof v'the tooth engaged by'thefeedingdog back past the said oppositel'y movable feeding i dogat each.operation of said back-spacing means. v l

, 16.l In a typewriting machine, a, carriage support, a Areciprocableplaten carriage spring-driven in one direction and mounted. on saidsupport, a -feed rack heldqto thecar-` riage, a'feed pinion meshing-Withsaid rack, a toothed escapement Wheel held to rotater with said pinion,la pivoted dog carrier, 'a

holding dog on said carrier, ay feeding-dog:

pivoted on'said carriei'vto" swing in opposite directions froma centralnormal position, a pair of controllers pivotally mounted on thedog'carrier andloosely engageable bythe feeding dog at different sidesofits pivot, a

tension spring connect-ingl said controllers-to,-

adapt the saine to arrest the feeding dog in central position, stops onthe carrier engageable by the controllers to limit pivotal movement 'ofthe controllers under thepuil of said spring, awstopon the carriert'orarresting pivotal movement ofthe feeding dog from central position by atooth of the escapement Wheel upon rotation of said Wheel under theinfluence of the carriage driving spring While said dog and tootharestill engaged, a spring connected with the dog Carrier for normallyrholding the carrier in position for engagement of the feeding dogvvit-h a tooth vof the escapement Wheel, and characterkey-operated'means kfor rocking thel carrier to. a posi- :tion.in'vvliich the' feeding vdogy released Trl 00 from and the holding dogengaged by a tooth of said Wheel. Y l

17. In a typeWriting machine, a carriage support, a reciprocable platencarriage spring-driven in one direction and mounted on said support, afeed'raclr held to thecarriage, a feed pinion meshing With said rack, atoothed escapement Wheel held to rotate With said pinion, a pivoted dogcarrier, a holding dog on said carrier, a feeding dog pivoted onsaidcarrier to swing in opposite directions from a central normal position,a pair of Y controllers'pivotally mounted on the dog carrier and looselyengageable by the feeding dogat different sides of its pivot, a tensionspring connecting said controllers to adapt the same to arrest thefeeding dog in central position, stops on the carrier engageable by thecontrollers to limit pivotal movement of the controllers under the pullof said spring, a stop on the carrierfor arresting pivotal movement ofthe feeding dog from central position by a tooth of the escapement Wheelupon rotation of said AWheelunder the infiuence of the carriage drivingspring rWhile said dog and tooth are still engaged, a spring connectedWith the dog carrier for normally holding` the carrier in position forengagement of the feeding dog `With a tooth of the escapement Wheel,character key-operated means for rocking the carrier to a position inwhich the feeding dog is released from and the holding dog engaged by atooth of said- Wheel, and a back-space-lrey-operated backspacing dogshiftably mounted on the carriage support normally disengaged from saidfeed rack and operable upon depression of the back-space key to engageand move the rack infopposition to the carriage driving spring adistance suiiicient-to force one tooth of the escapement-Wheel back pastthe feeding dog.

18. In a typewriting machine, a'traveling platen carriage, a toothedescapement member connected with the carriage, a pivotally supported dogrocker, a pair of escapement dogs on said rocker engageable alternatelywith said member, stopping means for determining the normal positionr ofthe rocker, a spring connected With the rocker and urging it to normalposition, key-operatedv means loosely engageable with the rocker formoving the rocker from normal position, an overthrow-preventing stop forsaid key-operated means, and a spring-held overthrow-preventing stopengageable by the dog rocker to arrest the same with the normallydisengaged dog in position for engagement With'. the toothed escapementmember. Y V

19. In a typewriting' machine, a traveling platen carriage, a toothedescapement member connected with the carriage, a pivotally supported dogrocker, a pair of escapement dogsV on said rocker engageable alternatelyWith said member, stopping means for determining the normal positionofthe rocker, a

spring connected with the rocker and urging it to normal position,key-operated means loosely engageable withy the rocker for moving therocker from normal position, an overthrow-preventing stop for ysaidkey-operated means, a spring-held overthrow-preventing stop engageableby the dog rocker to arrest the same With the normally disengaged dog inposition for engagement with the toothed escapement member, said springheld stop being operativeon the dog rocker upon movement of said stop inopposition to its spring to swing the dog rocker to a position in whichthe toothed. escapementmember is free from the contrai of the dogs, andmeans for at vWill moving said stop in opposition to its spring.

20. In a typewriting machine, a platen carriage, an escapement r'for thecarriage including a dog roclrer,an overthrow preventing device f-or thedog rocker, and hand-operated means for manipulating said device tocause the same to shift the dog` rocker to a position in which thevcarriage isfree from the lcontrol of the escapement.L

21. In an escapement mechanism, a toothedv member normally urged in onedirection, a

vibratory dog carrier, dogs on said carrier co-operative with saidmember to feed the saine step by step, means for vibrating the carrier,a device co-operative With the carrier l to normally prevent overthrowofthe carrier, and hand-operated means for manipulating said device toimpart an excessive movement to the carrier at Will to release, thetoothed member from the control of the dogs.

22. In an escapement mechanism, a toothed escapement member normallyurged in one direction, a vibratory dog carrier, dogs on said carrierco-operative-With rsaid toothed member to control the feed thereof,means cooperative lWith the carrier to limit its movement in oppositedirections to prevent aceidental freeingof said member from the controlof the dogs, said means including a shiftable device normally held inpositionfor engagement thereof by the dog carrier to prevent overthrovvof the Clog carrier in one direction, and manually operable escapeinentLreleasing means connected with said device for forcing said deviceVagainst a part of the dog carrier in a direction to positively move thedog' rocker beyond tlie point at which it is normally arrested by saiddevice.

23.' In an escapement mechanism, a pivoted dog carrier, a device pivotedtosiving about an aXis parallel With the pivotal axis of the dogcarrier, said carrier having' spaced abutments'betvveen Which saiddevice extends, aV spring urging said device in one'direction, means'for holding said device yagainst the tension of said spring in aposition to coact With one of said abutments to arrest movement of thedog carrier in one direction to prevent overthrow of the carrier, andman nelly operable eseapement reieasing means toothed along its edge toform a feed rack for vthe carriage escapenient. 1

by itsV spring, said feeding dog normally en@V gaging a tooth of saidmember, key-operated tappet means for rocking the rocker against thetension' of its spring, a device pivoted` on said rocker support toswing about an axis parallel with the pivotal axis of the rocker andextending between said arm and a rigid part of the rocker,ra springconnected with said device normally urging the same away' from said armagainst the rocker support, said device being normally held spaced from.said rigid part of the rocker by the rocker support in position toarrest movement of the rocker by said tappet means when theholding dogreaches a position forr engagement with the toothed member, andhand-operated release means connected with said device to swing thedevice in opposition to its connected spring to rock the dog rockerthrough the medium of said stop arm a distance sufficient to carry bothdogs out of cooperative relation with the toothed member. 5

25. ln a typewriting machine, a platen carriage having a base plate, Vametal member comprising two webs disposed substantially at a right angleto each other, screws detach-v ably holding one web ofsaid memberagainst one edge of the carriage base plate with theV other web of saidmember extending under the base plate, and a carriage bearingroller.

rotatably held to said screwfheld web, the web extending under the `baseplate oeing 26. In a typewriting machine,` a platen ear'-A riage havinga base plate, a metal member comprising two webs disposed substantiallyat a right an Ole to'each other, screws detach-vv n Ab..- o a ablyholding one web of said member against one edge of the carriage basevplate with'the other web of said' member extending under,

the base plate, a carriage bearing roller-rotatably held to saidscrew-held web, the web extending under the base plate being toothedalong its edge-to form a feed vrack for the can riage escapement, and arotary escapement de ffice geared to said rack.

A In a typewriting machine, a platen car-` riage having va base plate,lametal member comprising two webs disposed substantially at a right angleto each other, screws detachable holding one web of said member againstVoneedge of the carriagebase plate with-thel other web of said memberextending under the base plate, a carriage bearing `roller rotatablyheldto said screw-heldweb, the webl extending under the base plate beingtoothed along its edge to form a feed rack for the carriage escapement,a support for the carriageA having a track `thereon for said roller, abracket detachablylield to saidl support, a shaft journalled on saidbracket, a feed pinion on said shaft meshingwith vsaid feed rack, anescapement wheel on said shaft, a dog rocker mounted on said bracket,and dogs on saidrocker cooperative with said wheel.A

28.. In an escapement, an assembly comprising asheet metal brackethaving a flat body part formed with depending end portions and havinganopening in said body' part, a bushing extending throughl andv swagedinsaid opening, a shaft yextending through said bushing and having anintegral feed pinion formedI on lits upperend, said shaft having acollar thereon seated on the upper end of said bushing anda reducednon-circular lower end portion projecting below the `lower end of thebushing, a sheet metal escapeinent wheel' abutting :the lower end ofthebushing and having a central opening in which said reduced endportion ofthe y shaft is engaged, said wheel opening con-k forming to the contourof said reduced end,

portion of the shaft, said shaft having a threaded axial bore at itslower end, a washer abuttingthe end of theshaft and the under face V'ofsaid wheel, and a retaining* screw having a shank-passing upwardlythrough saidwasher and screwed into said bore.

v29'. In'an escapement, an assembly comprising a sheety metal brackethaving a flat body part formed with dependingv end portions and havinganV opening insaid body,

part, a bushing extending through and swaged in saidopeninfr, a` shaftextending,

throughsaid bushing and having an integral feed pinionformed onritsupper end, said shaft having a collar thereon seated on the: upper endof saidbushing anda reduced non-- circular lower end portionprojecting.below.`

thelower end ofthe bushing, a sheet metal escapeinen-t wheel abuttingthe lower end of of the shaft, said shaft having ay threaded.

r the bushing'and having a central opening axial bore at its lower end,a washer abutting the end of the shaft and the under face of said wheel,a retaining screw having asliank pass ing upwardly through Y said washer1 and screwed into said bore, a sheet metal dog roeker pivotallysupported on the depending end portions of the bracket, holding andfeeding 30. In a typewriting machine, a carriage bed, a platen carriage,affeed rack held to the carriage, an escapement releasingbail pivoted onthe carriage, a bracket detachably held to the bed, a dog rocker mountedon the bracket, a shaft 'journalled on the bracket, a feed pinion onsaid shaft meshing with said rack, an escapement wheel on said shaft,escapement dogs on the rocker cooperative with said wheel, a devicepivoted on thebracket.

and loosely engaged by said bail and operable by the bail to rock thedog rocker for releasing the escapement, and a stop on the dog rockerengageable with said device to prevent overthrow of the dog rocker inone direction. v

3l. In a typewriting machine, a carriage bed, a. carriage mounted on thebed to travel therecver, a feed rack held to the carriage and locatedbetween the carriage and bed,a bracket detachably held to the under faceof the bed, a shaft journalled on said bracket and extending through thebed, a feed pinion on said shaft between the carriage and bed meshingwith rsaid rack, said bed having an opening through which said pinionmay pass, an escapement wheel on the lower end of said shaft, a dogrocker pivoted on said bracket, a release bailfpivoted on the ends ofthe carriage to swing fore-and-aft and having its cross bar'extendingbetween the carriage and bed, holding and feeding dogs on the rockercooperative with said wheel, a lever pivoted on the bracket on a pivotextending trans- Y versely of the machine and having one arm extendingupward through the bed and loosely engaged by the cross-bar of therelease bail and an arm below the bed arranged to impart an excessivetripping movement to the dog rocker, and a return spring for said leverand bail connecting the lever with the bracket.

32. In a tjpewritino machine, a carriage bed, a carriage mounted on thebed to travel thereover, a feed rack held to the carriage and locatedbetween the carriage and bed, a

bracket held to the under face of the bed, a

shaft ournalled on said bracket and extendiiigthrough the bed, a feedpinion on said shaft between the carriagerand bed meshing with saidrack, an escapement wheel on the lower end or" .said shaft,.a dog rockerpivoted on'said bracket, a release bail pivoted on the ends of thecarriage to swing fore-and-aft and having its cross bar extendingbetween the carriage and bed, holding and feeding dogs on the rockercooperativey with said wheel, a lever pivoted on the'bracket on a pivotextending transversely of the machine and' having one arm extendingkupward through. the bed and engaged'by thecross-bar of the release bailand an arm below the bed arranged to impart an excessive trippingmovement to the dog rocker, a return spring for said lever and bailconnecting the lever with the bracket, a back-spacing dog mounted rigidand pivoted dogs on said carrier en-.

gageable alternately with said toothed member, a return spring urgingthe dog carrier in one direction about its pivot, a stop arm rigidlyheld to the dog carrier normally engaging a stationary part of themachine to arrest movement of the dog carrier by its return spring withone of said dogs in position for engagement with said toothed member, auniversal bar, means operable by said universal bar for rocking the dogcarrier in opposition to its return spring, a stop member pivotallysupported independently of the dog carrier and carriage and engageableby the dog cai'- rier to arrest the dog carrier with the other dogthereon in position for engagement with the too-thedmeinber, and aspring connected with said pivoted stop member to resist movement of thestop member when engaged by the dog rocker and normally holding the stopmember against afixed part of the machine to determine the normalposition of said stop member.

34:. In a typewriting machine,'a traveling platen carriage, a toothedescapeinent inember connected with the carriage and springurged in onedirection, a dog carrier pivotally supported independently of thecarriage to rock about an axis parallel with the path of travel of thecarriage, rigid and pivoteddogs on said carrier engageable alternatelywith said toothed member, a return spring urging the dog carrier in onedirection about its pivot, a stop arm rigidly held to the dog carriernormally engaging` a stationary part of the machine to arrest movementof the dog carrier by its return spring with one of said` Vdogs inposition for engagement with said toothed member, a universal bar, meansoperable by said universal bar for rocking the dog carrier in oppositionto its return spring, a stop member pivotally supported independently ofthe dog carrier and carriage to rock about an axis parallel with thepivot-al axis of the dog carrier and engageable by the dog carrier toarrest the dog carrier with the other dog thereon in position forengagement with the toothed member, aspring connected with said pivotedstop member Vto resist movement of the stop member when engaged by thedog rocker and normally iolding the stop memberagainst a fixed part ofthe machine to determine the normal position n of said stop member, anda hand-operated escapementreleasing member pivoted on the carriage toable by the carrier to limit movement of the carrier in one direction toprevent accidental release ofthe escapem'ent by an overthrow of thecarrier and a part thereof eno'ageable with the carrier tov move thecarrier in said direction to overthrow the carrier, hand-operableescapement-releasing means associated with said member to shift themember to ren- -der said first mentioned part ineffective on the carrierand the second part effective on Vthe carrier to shift the carrier to anoverthrown position inwhich the toothed member is free from the controlof said dogs, and means normally holding said member in its position forpreventing overthrow of the carrier. f 1

42. In a typewriting machine, a springdriven platen carriage, a toothedmember -driven with the carriage, a vibratory dog carrier mountedindependently of the carriage having two parts spaced in the directionof motion of the carrier, escapement dogs on said carrier cooperativewith said toothed member, a shiftable member supported independently ofthe carriage extending between said spaced parts of the dog carrier andnormally cooperating with one of said parts to prevent overthrow of thecarrier, and hand-operable means mounted on the carriage to traveltherewith and engage-l able with said shiftable member in all positionsof thecarriage adapted to shift said member fromV its normal position,said shiftable member when shifted by said hand-operable meanscooperating with the other of saidY spaced parts on the dog carrier toover throw Athe carrier'V and thereby free the toothed member fromthe'lcontrol of said dogs. Y

43. In an escapement mechanism, a sheet metal dog carrier having a flatbody part formed with integral pendent pivot ears at its ends and anintegral holding dog at one edge thereof,L one of said ears havingformed thereon an integral stop arm extending above the plane of thebody part of the rocker and an integral pendent arm lying flatwise inthe plane ofV said ear and having its lower end A bent up at right anglethereto t-o Yform a contact lugfo-r engagement by an operating.

tappet. y y

44, 'ln an escapement mechanism, a sheet metal dog carrier having a flatbody part` formed with integral pendent pivot ears at its ends and anintegral holding dog at one edge thereof, one of said ears having formedthere on an integral stop arm extending above the for attachment of acarrier return spring thereto. Y

45. In a typewriting machine, a traveling carriage spring-driven in onedirection, a carriage support, a sheet metal bracket having a flat'bodypart held to said support and provided with pendent side members, a rackheld n to the carriage, a shaft ournalled on the bracket and extendingthrough the fiat body part thereof, a feed pinion fixed on the upper endof said shaftmeshing with said rack,an escapement wheel fixed on thelower end of said shaft, a sheet metal dog rocker having a fir-tbodypart formed with pendentv pierced pivot ears at its ends, pivot screwsfor said rocker threaded through saidmembers of the,

bracket and having bearing portions engaged 1n the apertures in saidrocker ears, an integral holding dog projecting from one edge of thebody part of the rocker, a feeding dog projecting from the same edge ofthe rocker, a pivot screw for said dog threaded into the flat body partof therocker, one of the pivot ears of said rocker having anintegralstop arm normally engaged with said bracket to limit upward swinging ofthe rocker and an integral pendent arm, a rocker return spring' feed dogand threaded into the body part ofV the carrier, a pair of sheet metallevers, pivot screws extending through Vsaid levers and threaded intothe body part of said carrier at opposite sides of the feeding dog, saidlevers having inwardly extending arms and arms atV an angle to theinwardly extending arms, a

tension spring connecting the last-mentioned.

lever armsand urgingy the inwardly extending lever arms toward thelaterally extending` feeding-dog arms, and a pair of integralstopsformed on the body part of the dog car-` rier engaged by said levers tolimit movement of the levers by the spring, said inwardlyextending-lever arms engaging the feeding dog arms to yieldably resistmovement of the feed dog in both directions about its pivot when thelevers are engaged with said stops.

47. In a typewriting machine, a shift frame, a shift key connected toVshift said frame, a platen carriage shiftable with the shift frame,escapement mechanism or the carriage shiftable with the shift frame andincluding a pivoted dog carrier, a pivoted member shiftable with theshift frame and

